Let's face it, there's really no point in DDOSing this site to get the information. All you'll do is bring the site down and leave you unable to verify if what you did worked or not, and that's kind of pointless, isn't it?
Therefore, no DDOSing. It wouldn't help you solve the problem easier, trust me. Attacking it with many computers isn't the way to go. Attacking it with your brain works though *hint Hint*
For those who don't know, bruteforcing is basically constantly trying and sending stuff to the server hoping you get it right. The most common example is a password field, where people keep on guessing passwords one by one until they hit it.
Well, in this case, bruteforcing might work in getting the answer, but don't do it. Why? Becuase the rules say so. That's why. And because by bruteforcing, you're already sending a lot of requests to the server, thereby overloading the server and bringing it down. See above to why that is bad.
Oh, and also becuase the point of this CTF is for you to learn how to get pass certain challenges, how to reverse engineer the website or the source to try to get past it. Bruteforcing isn't really teaching you that, and thus you're not learning anything.
There are no more rules
At first look, this rule may seem stupid. It looks like there's kind of no point putting it there. "There are no more rules". Isn't it obvious? If you didn't put the rule there, doesn't it mean the same thing? What's up with that?
Well, firstly, if this rule wasn't there, there would be only 2 rules, which isn't really strong. See the rule of three.
However, the real reason is that this rule clearly states that there are no more rules. You will become very irritated on trying to solve the puzzle if you keep on constraining yourself and thinking at a certain angle.
Remember, there are no more rules. Anything might be creating the challenge, and something else may solve it. It may not be what you are thinking of at the time. Don't be afraid to try other tactics or look elsewhere.
Do not constrain yourself in thinking a certain method is the only way to solve the challenge. It's very likely it's not.